Engine starting apparatus



Jan. 30, 1962 H. THOMPSON 3,018,768

I ENGINE STARTING APPARATUS Filed Feb. 9, 1960 2 Sheets-Sheet 1 TII3INVENTOR HOWARD H.THOMPSON M W /W ATTORNEY Jan. 30, 1962 H. H. THOMPSON3,013,768

ENGINE STARTING APPARATUS Filed Feb. 9, 1960 2 Sheets-Sheet 2 lllllliMINI- TIE: 3

lll- I T k l INVENTOR HOWARD H. THOMPSON av W ATTORNEY United States.PatentO 3,018,768 ENGINE STARTING APPARATUS Howard H. Thompson, SanJose, Calif., assignor to FMC Corporation, a corporation of DelawareFiled Feb. 9, 1960, Ser. No. 7,633

5 Claims. (Cl. 123-185) This invention relates to engine-poweredgardening machinery and more particularly relates to starting apparatusfor the engines of such machinery.

An object of the invention is to provide improved apparatus for startingpower gardening machines.

Another object is to provide improved starting apparatus having anadvantage with respect to the length of pull required to start theengine of greater than 1: 1.

Another object of the invention is to provide an improved kick-starterfora power lawnmower, i.e., a starter enabling a person to start theengine of the lawnmower by means of a foot-actuated lever.

These and other objects and advantages of the invention will be apparentfrom the following description and the accompanying drawing wherein:

FIG. 1 is a partly broken away perspective of a power lawnmower havingthe starter of the invention operatively installed thereon.

FIG. 2 is a side elevation, partially in section, of the lawnmower ofFIG. 1 and illustrates two operational positions of the starter. v p

The power lawnmower (FIGS. 1 and 2) comprises a housing or framework 12having four wheels 14 rotatably mounted thereon, and an engine 16. Theengine 16 is centrally mounted on the lawnmower framework 12 and extendsa .short distance through a suitable central opening 18 in the housing.The engine includes several foot members 20, which project over thehousing 12 ad jacent the opening 18 and support the engine on theframework. A bolt 22 passes through each foot member to fasten theengine to the framework 12. A handle 24 for the lawnmower is connectedto the framework 12 by suitable axially aligned pivot pins such as thebolt 26 (FIG. 2).

Connected to the engine crankshaft 28 (FIG. 2) are an engine crankingmechanism 30, a flywheel 32, and a grasscutting blade 34. A nut 36connected to the end of the crankshaft 28 retains these members in theiroperating positions. The engine cranking mechanism 30 is not shown indetail but comprises what is known in the art as a recoil starter andincludes a cranking pulley 31.

Recoil starters used on small engines are usually provided with a pullrope which is pulled briskly by hand, to crank the engine. In closequarters or in situations where the operator is requiredto assume anawkward position, suchpull ropes cannot be operated satisfactorily. Theadvantage with respect to length of pull provided by the startingapparatus of the present invention permits small engines to be easilycranked even in close quarters and without liability of injury to theoperator.

The pull rope or starting cable 38 of the engine 16 has one end thereofoperably connected to the recoil starter 30 from which the rope extendsthrough an opening 40 in the engine casting. The other end of the cable38 is securely fastened to the framework 12, as by passing it through asmall hole 42 in the framework and. then tying a knot 44 in it, as shownin FIG. 2. A sheave or pulley 46 engages the cable between the opening40 and the hole 42, thus forming a loop, or bight 47 in the cable. Thepulley 46 is mounted on a pin 48 in one end of a lever 50. The lever 50is pivotally mounted on a bolt 52 which is carried in a bracket 54welded or otherwise connected to the housing 12 ofthe lawnmower. A treadbar 56 is connected to the lever 50 at the end opposite the pulley 46.

To crank the engine 16 the tread bar 56 is depressed 3,018,768 PatentedJan. 30, 1962 2 from its initial position (FIG. 1, and phantom lineposition in FIG. 2) to its alternate position (solid line position inFIG. 2). Depression of the tread bar 56 causes the pulley 46 totranslate or bodily move in an arcuate path around the bolt 52. Inmoving, the pulley causes the rapid withdrawal of the cable 38, spinningthe internal mechanism of the cranking mechanism 30 so as to crank theengine 16.

The lever 50 is, of course, adapted to be operated by foot and with thedisclosed arrangement the operator can with little effort, and withoutstooping or otherwise assuming an awkward position, impart a startingimpulse to the engine. When'the operator removes his foot from the treadbar 56 the lever is automatically returned to its initial position(FIG. 1) by the action of the recoil starter 30 rewinding the cable 38.

Since the apparatus of the present invention actuates the starter by theuse of a pulley engaging a bight portion 47 of the pull rope, the pulleyend of the lever need travel only one half the distance to turn thecranking mechanism and therefore it attains an advantage with respect tolength of pull of approximately 2:1 as compared to the 1:1 ratioprovided by conventional starting devices wherein a single reach of apull rope is withdrawn by hand. Other lever lengths and other pulleyarrangements are variations which could be used to change the pressurerequired to operate the device and to change the ratio of the mechanicaladvantage attained thereby. The apparatus can be used for starting anyengine of reasonable size.

While a particular embodiment of the present invention has been shownand described it will be understood that the device is capable ofmodification and variation without departing from the principles of theinvention and that the scope of the invention should be limited only bythe scope and proper interpretation of the claims appended hereto.

The invention having thus been described, that which is believed to benew and desired to be protected by Letters Patent is:

1. In a gardening machine having a frame, an engine mounted on saidframe, and a cranking mechanism connected to said engine, thecombination of a cable having one end thereof operatively connected tosaid cranking mechanism and the other end thereof fixed to the frame,and a foot-operated lever mounted for movement relative to said frameand having a portion operatively engaged with said cable intermediatesaid cable ends and movable along a path transverse to a line passingthrough said points of connection for imparting a starting impulse tothe engine.

2. In a machine having an engine and an engine cranking mechanismincluding a starting pulley, the combination of a starting cable havingone end thereof wound on said pulley and having the other end thereoffixed, a sheave engaging a bight of the starting cable between saidends, and foot-operated means mounted on said machine for bodilyshifting said sheave in a direction away from the starting pulley tounwind the cable therefrom to rotate the pulley and thereby impart astarting impulse to the engine.

3. In a gardening machine having a frame, an engine mounted on saidframe, and a cranking mechanism operatively connected to said engine,the combination of a starting cable having one end thereof operativelyconnected to the cranking mechanism and having its other endimmobilized, a pulley operatively engaged with the starting cable, and afoot-operated lever connected to said pulley for translating the pulleyin a manner drawing the cable from the cranking mechanism to impart astarting impulse to the engine.

4. Starting apparatus for a gardening machine having an engine mountedon the frame thereof and a cranking device connected to the engine, saidapparatus comprising a foot-operated lever, a starting cable having oneend thereof operably connected to the cranking device and having theother end thereof fastened to the frame, and a pulley journalled on saidlever and operatively positioned to pull the cable and thereby impart astarting impulse to the engine upon foot operation of said lever.

5. In a gardening machine having a frame, an engine mounted on saidframe, and a cranking mechanism operatively connected to the enginecrank shaft, the combination of a starting cable having one end thereofoperatively connected to said cranking mechanism and having the otherend thereof fastened to said frame, a foot- References Cited in the fileof this patent UNITED STATES PATENTS 1,327,942 Christie et al. Jan. 13,1920 1,553,780 Keeler Sept. 15, 1925 2,293,322 Veach Aug. 18, 19422,850,003 Konle Sept. 2, 1958

